Revert of Keep track in the browser of which frames have onunload and onbeforeunload handlers.

content/common/frame_messages.h

Index: content/common/frame_messages.h
diff --git a/content/common/frame_messages.h b/content/common/frame_messages.h
index fbd56f7dbd3e17bc05d28a69879517dfd5950405..002ae95d94d653cd5f2520a22320eb8cd5368b7b 100644
--- a/content/common/frame_messages.h
+++ b/content/common/frame_messages.h
@@ -1611,13 +1611,6 @@ IPC_MESSAGE_ROUTED1(FrameHostMsg_HittestData, FrameHostMsg_HittestData_Params)
 // FrameMsg_RunFileChooserResponse message.
 IPC_MESSAGE_ROUTED1(FrameHostMsg_RunFileChooser, content::FileChooserParams)
 
-// Messages to signal the presence or absence of BeforeUnload or Unload handlers
-// for a frame. |present| is true if there is at least one of the handlers for
-// the frame.
-IPC_MESSAGE_ROUTED1(FrameHostMsg_BeforeUnloadHandlersPresent,
-                    bool /* present */)
-IPC_MESSAGE_ROUTED1(FrameHostMsg_UnloadHandlersPresent, bool /* present */)
-
 #if BUILDFLAG(USE_EXTERNAL_POPUP_MENU)
 
 // Message to show/hide a popup menu using native controls.